in regard to the chemical or is technology being developed by the calledent of defense terahertz technology. i can scan for chemical traces down to small choices that you may have come into contact with accidentally. evil can be triggered as potential -- people can be triggered as potential targets. individuals and commercial companies are allowed to use drones -- if utilities use them to detecting meters or obtain video on private property, are there limitations on whether law enforcement can ding those videos to absolute a warrant? >> unless the officers instructed the private individuals to do surveillance, no, they would not need a warrant for that. to fourth amendment applies state actors. there are limitations that will apply to private parties and not the government. surveillanceerial case involving trade secrets that was thought to violate law although it did not violate the fourth amendment. regard to the first amendment, i have several restaurants. with regard to commercial applications, we have heard concerns about the use of private data are collected by companies for advertisin